Means for withdrawing dust and fumes from zinc or similar furnaces.



E. DOR DELATTRE.

MEANS FOR WITHDRAWING DUST AND FUME'S FROM ZINC 0R SIMILAR FURNACES.

-AFPLIGATION FILED JUNE 19, 1908.

Patented May 30, 1911.

a .w K W STATES EMILE DOB. DELATTRE, 0F LIEG'E, BELGIUM.

MEANS FOR WITHDRAWING DUST AND FUMES FROM ZINC 0R SIMILAR FURNACES.

Specification of Letters Patent.

To (ZZZ whom it may concern:

Be it known that I, EMILE DOR DELATTRE, engineer, subject of the King of Belgium. residing at Liege, Belgium, have mvented certain new and useful Improvements in Means for WVithdrawing Dust and Fumes from Zinc or Similar Furnaces; and do hereby declare the following to be a full, clear, and exact description of the invention.

The present invention relates to means for producing, without the expenditure of power, an effective and continuous suction or exhausting draft for the purpose of extracting or removing dust and fumes created by zinc furnaces, retort houses and the like.

The invention consists in the particular arrangement of two concentric shafts or chimneys, of which the one serves for the discharge of the products of combustion of the retort-heating furnace while the other is in communication with the fines and chambers or apartments of the retort house or the like from which the dust and fumes are to be removed and is so arranged as to be inductively influenced by the combustion products that ascend the furnace shaft.

The accompanying drawing represents one arrangement according to this invention.-

Figure 1 is a part vertical section. Fig. 2 is a sectional plan on AB, and Fig. 3 is a sectional plan on CD (Fig. 1).

The arrangement as applied to a zincextraction furnace, consists essentially:

1. Of a main stack, shaft or chimney aof masonry, communicating with the upper portion of the furnace or retort-house by the flue b, and also, through the opening d, with the closed chambers 0 which receive the residues discharged from the retorts when the latter are cleaned. This chimney a serves to exhaust and carry off the dust and zinc fumes which are evolved from the furnace during the different operations. The flue b and the opening (Z are provided with dampers e, for regulating or controlling the action of the draft on the retort-house or furnace fines and on the residue chamber and so that either part may be cut off fromthe stack when desired.

2. Of a sheet metal or other inner chimney or shaft f, suspended by the cross-piece it within the interior of the masonry chimney or stack a. This chimney h, which serves to discharge the products of combustion of the retort-heating furnace, can expand freely at its lower end, which is adapted to slide within a cast-iron ring 1' fixed in the Patented May 30, 1911.

Serial No. 439,394.

lower part of the masonry. The said inner chimney communicates with the furnace by the flue 7c and extends to a height approximately equal to two-thirds of the chimney a,

, so that its upper end terminates at a pointabout one-third of the total height below the top of the said chimney a. The products of combustion, which issue from the furnace at a temperature of about 300 0., pass directly through the flue 70 into the sheet-metal chimney f. This passage of the hot gases into the chimney f induces a strong draft in the chimney a from two causes: viz :-first, because the air which 1s contained in the annular space between the two chimneys is heated by the hot gases passing through the inner chimney f and is thereby made to ascend and create a draft in the masonry chimney a; and, secondly, because the chimney f acts as a draft accelerator. The gases issuing from this chimney f with a certain velocity, exert a pull upon the air in the chimney a, or induce an action similar to that which would be set up if an injector were placed in the interior of this chimney. The dampers c moreover permit of directing the suction produced by this system of chimneys either from the top or from the bottom of the furnace, according to the necessities of work; they also allow of regulating the draft.

It can be seen that the apparatus above described, can produce continuously, and without the expenditure of power, a powerful exhausting draft which can be easily controlled, and is applicable to a variety of industrial plants.

I am aware that it has been heretofore proposed to provide dwellings or houses with ventilating chimneys comprising a central smoke flue and an outer or surrounding flue through which currents of air can be drawn from the interior of the building by a draft caused by the passage of products of combustion through the central smoke flue and therefore do not make any claim broadly for such a device. However, so far as I am aware, a zinc or similar furnace has never been provided with such a means for withdrawing fumes or dust as I have described in the foregoing specification and illustrated in the accompanying drawing and as will be well understood and appreciated, the importance of such an attachment to a furnace of this character cannot be over estimated. The fumes and gases produced by the operation of furnaces of the character referred to are very offensive and injurious to the operatives and it is of greatest importance that they be removed if possible. By the present invention a practically complete and thorough exhausting of the objectionable fumes, gases and dust from the chambers of a zinc furnace is effected without material expense and without requiring any attention from the operatives or workmen. Furthermore, the manner of supporting the internal combustion flue described and illustrated is quite different from the construction and arrangement of similar parts of the ventilating chimneys before referred to. Accord ing to this invention, such inner smoke flue is supported entirely at its upper end.

In the ventilation or heating of dwelling rooms or apartments, it is absolutely necessary that there be no violent movement of the current of air. Therefore the ventilating chimneys are designed and adapted to effect merely a slow movement of relatively small quantities of air, and are consequently not adapted for the purpose of my invention. The apparatus at present employed to carry off the dust and fumes from zinc or other metallurgical furnaces include powerful blowers in order to obtain the necessary strength of suction. Such apparatus is objectionable both because of the expense and the energy or power which is required to operate it. My invention however, utilizing merely the waste heat of the furnace, provides a constant strong suction which effectually carries away the fumes and dust produced by the furnace. To accomplish this it is necessary that the apparatus differ in two important particulars from chimneys designed for ventilatin dwellings, etc. First, in order to carry off the dust and fumes it is necessary to move a very large volume of air through the chimney, to provide for which the exterior member of the chimney is made of considerably greater diameter than the inner member. Secondly, the movement of air through the chimney must be very rapid or violent, and therefore the gases admitted to the inner flue are very hot.

Having fully described my invention, what I desire to claim and secure by Letters Patent is 1. The combination with a zinc or similar furnace having two vertically separated passages the upper one arranged to receive fumes generated in the furnace and the other communicating with the chamber of the furnace wherein relatively heavy solid particles of dust from the retorts, crucibles, etc., collect, of a stack or chimney communicating with both said passages, and a flue arranged within the stack and adapted to receive the highly heated gases escaping from the combustion chamber of the furnace, the heights and diameters of the stack and flue being so proportioned that a large volume of air is caused to move rapidly through the space separating them and effectually carry off both the fumes and the relatively heavy dust produced by operating the furnace.

2. The combination with a zinc or similar furnace comprising a retort or crucible chamber, an upper chamber communicating with the retort chamber and receiving the fumes generated by the furnace when in action, and a lower chamber which receives solid dust particles separated from the retorts or crucibles while being handled and cleaned, of a stack or chimney communicating directly with both said upper and lower chambers through independent openings, and a flue arranged within the stack and adapted to receive the highly heated gases escaping from the combustion chamber of the furnace, substantially as and for the purpose described.

8. The combination with a Zinc or similar furnace, of a chimney comprising two concentric flues, the inner one communicating with the combustion chamber of the furnace and adapted to carry off the products of combustion therefrom and the outer flue communicating with a chamber or chambers from which it is desired to withdraw fumes or dust, said inner flue being supported entirely above its lower end.

4. The combination with a zinc or similar furnace, of a stack communicating with the chamber or chambers of the furnace from which it is desired to withdraw dust or fumes, a flue suspended within said stack, and a duct communicating with the lower freely swinging end of said flue and adapted to conduct products of combustion from the combustion chamber of the furnace to said flue.

5. The combination with a zinc or similar furnace, of a masonry stack or chimney communicating with the chambers of the furnace from which it is desired to withdraw dust or fumes, said stack being of less diameter at its upper end than at its base, and a metal flue, of uniform diameter throughout its length, supported within the stack and having its lower end free to move relative to said stack, said metal flue communicating with the combustion chamber of the furnace.

In testimony whereof I aflix my signature in presence of two witnesses.

EMILE DOR DELATTRE.

Witnesses A. MAmioHAL, T. GABRIEL.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents,- Washington, D. C. 

